Friction latch mechanism



June 5., 1962 c. E. HAFSTAD FRIcToN LATCH MECHANISM Filed Jan. 25, 1961FI c. I

IN VEN TOR. OAHL E. .HA/rs 'rAo QZM .A T TO F1 N E YS 3,037,801 FRICTIGNLATCH MECSM Carl E. Hafstatl, 828 21st Ave. S., Minneapolis 4, Minn.Filed Jan. 25, 1961, Ser. No. 84,829 8 Claims. (Cl. 292 76) Thisinvention relates generally to door latch mechanisms, and moreparticularly it relates to an improved and useful friction catch of atype which will yield under the application of force, as distinguishedfrom the more positive type of locking catches.

More specifically my invention relates to friction latch mechanisms foruse on storm doors and the like, which are usually provided withpositive locking mechanisms. It is very often true that when doors ofthe above described class are provided with positive locking means, theyare prevented from making locking engagement by the air pressure builtup between the same and the inner door or other door with which they areassociated, said pressures either being created by the closing movementsof one or the other of said doors. Of course, under such conditions itis very possible that a situation is presented which the storm door mayeasily be broken or otherwise damaged since the same is not in apositively locked condition. In light of the above, it is an importantobject of this invention to provide an improved friction latch mechanismwhich may be used either with or without conventional positive lockinglatch mechanisms to overcome the conditions and disadvantages describedabove.

Another important object and advantage of this invention is the.provision of an improved friction latch mechanism in which the forcerequired to open the door with which it is associated is materiallygreater when certain parts or elements of said latch mechanisms aredisposed in one position or condition than the force required to opensaid door when said parts or elements of said latch mechanism aredisposed in another condition or position.

Another object of this invention is the provision of an improvedlfriction latch mechanism in which the above described greater oradditional force required to open said door when said latch mechanism isin a chosen position or condition may be easily and quickly reduced oravoided by the person opening the door.

Another object of this invention is the provision of an improvedfriction latch mechanism in which the same is adjustably and removablymaintained in said position or condition wherein a materially greaterforce is required to open said door, and in which the maintenance ofsaid additional force may be easily and quickly rendered inoperative bythe operator of said latch mechamsm.

Other objects of this invention reside in `the provision of an improvedfriction latch mechanism which is eX- tremely simple in construction,relatively inexpensive to manufacture, durable and strong throughout itscontinued use, simple and eicient in its operation, and highly ecient insustaining the above stated purposes.

The above and still further objects of this invention will becomeapparent from the following detailed specication, appended claims andattached drawings.

Referring to the drawings wherein like reference char- -acters indicatelike parts or elements throughout the several views:

FIG. l is a view of my invention in front elevation, and showingportions of cooperating door and jamb members with which my novelfriction latch mechanism is associated;

FIG. 2 is a view in section taken on the line 2 2 of FIG. 1, and showingmy invention substantially in side elevation, some parts being brokenaway;

FIG. 3 is a view in section taken on the line 3 3 of Patented June 5,1962 FIG. 2, and showing my invention substantially in rear elevation;

FIG. 4 is a view in section taken on the line 4 4 o-f FIG. `1 with someparts being broken away, and showing my novel latch mechanism in itsclosed position;

FIG. 5 is a view similar to FIG. 4, but showing the door member duringinitial opening movement thereof, and also showing portions of my novellatch mechanism in a position or condition resulting from opening of thedoor member from the outside thereof;

FIG. `6 is a View similar to FIG. 5, but showing said portions of mylatch mechanism in a position or condition resulting-from the opening ofthe ydoor member from the inside thereof, and ialso showing otherportions or elements of my invention in an alternative position;

FIG. 7 is a view similar to FIGS. 5 and 6, but showing the door member`during final closing movement thereof, and also showing portions of myinvention in their respective positions during nal closing movement ofthe door member; and

FIG. 8 is a view in horizontal section taken on the line 8 8 of FIG. -l.

Referring with greater particularity to the drawings, the door member,represented generally by the reference letter A, is movably mounted in ajam'b member, which is represented generally by the reference letter B.A conventional keeper elementi is rigidly secured to the inner face b ofthe jamb member B, near the outer edge c thereof, by means of a pair ofscrews 2. This invention resides speciiically in the provision of afriction catch, which is represented generally by the reference numeral3, the complete latch mechanism including the keeper element 1, beingrepresented generally herein by the reference numeral 4. Also, the innerface of the door member A is represented by the reference letter a, theout-er face thereof by the reference letter C, and the free edge of thedoor member A being represented Iby the reference letter e.

In accordance with my invention, the latch mechanism 4 comprises a rigidsupporting housing, represented generally by the reference numeral S,said supporting housing 5 including a front wall 6, an inner side wall7, a top wall 8, a bottom wall 9, and vsecurernent flanges 10 forrigidly securing the supporting housing 5, by means of the fasteners 11,to the inner face a of the door member A. It is noted that the back ofthe supporting housing 5 is generally open, and the supporting housing 5is also bifurcated at the outer side 12 thereof so as to define spacedand alignable spring-carrying flanges 13. As shown, a pair of elongatedcoil springs 14, 15 `are carried by the spaced anges 13 of thesupporting housing 5 so as to dispose the respective end portions 16, 17o-f said springs 14, 15 in a fixed relationship with respect to the doormember -A. It is noted that the respective end portions 16, 17 of thecoil springs 14, 15 are rigidly secured, as by welding or soldering, inthe respective positions shown particularly in FIGS. 2, 3, and 8, saidend portions 16 of the coil spring 14 being engaged with the arcuate endportions 18 of the flanges 13 and the end portions 17 of the coil spring15 being engaged with the corner defined by the flanges 13, and theouter side 12 and the front wall 6 of the supporting housing 5.

An important part of my invention concerns the respective positions ofthe elongated coil springs 14, 1S, and also the provision of means forselectively changing the respective positions between the coil springs14, 15'. More specifically, one respective position or condition of thesprings 14, 15 are disposed in generally laterally spaced generallyparallel relationship with one another. It is noted with particularlyemphasis that the coil springs 14, 1S when the same are in said onecondition are thereby so orientated that the coil spring 14'is engagedby the' keeper element 1 during initial opening movement of the doormember A with respect to the jamb member B so that lateral deflection isimparted to the spring 14 in a direction generally toward the spacedspring 15. Said engagement of the spring 14 by the keeper` element 1 andthe resulting deflection of the spring 14 during initial openingmovement of the door member A is shown particularly in FIG. 6,. It isnoted with emphasis that the opening force required to open the doormember A when the springs are in said spaced one condition is only theforce needed to deflect the coil spring 14 to the position shown in FIG.6 since the coil spring 15 is not deected in said one condition of thesprings 14, 15.

For the purpose of providing means for selectively ladjusting the coilsprings 14, 1S so as to define a second condition or relative positionof said coil springs 14, 15, a slide element, represented generally bythe reference numeral 19, is mounted on the supporting housing 5. Theslide element 19 generally comprises an elongated bar, which defines aprojecting knob '21 on one side thereof and a projecting dog 22 on theother side thereof. The knob 21 has a flange portion 23 which ismaintained in spaced relationship with the bar ofthe slide element 19 bymeans of a stub journal 24, said knob 21 being removably secured to theslide element 19 by means of a screw 25. As shown particularly in FIGS.l and 4, the front wall 6 of the supporting housing 5 defines anelongated slot 26, Vwhich slot 26 is adapted to receiveY .the stubjournal 24 ofthe slide element 19 sothat the bar of the slide elementl19 is disposed in face-to-face sliding relationship with the innersurface of the front Vwall 6 of the supporting housing 5 and so that theflange portion 23 of the knob 21 is disposed in sliding face-.tofacerelationship with the outer surface of the front wall 6 of thesupporting housing 5. Referring particularly to FIGS. 2 and 4, the slideelement 19 also defines an abutment surface 27 on the end thereofdisposed adjacent the Vcoil spring 15. The above described constructionis such that the slide element 195is thereby mounted on the supportinghousing for movement toward and away from the coil spring between aspaced position in spaced relationship to said coil spring 15 (as shownin FIG. 6) yand an engaged position (as shown in FIGS. 2, and 4)vwherein the abutment surface 27 of the slide element 19 is disposed inengagement with a generally intermediate portion 28 of the coil spring15. Such an engagement between the abutment surface 27 and saidintermediate portion 28 of the coil spring 15 into engagement with thecoil spring 14 and thereby defines a second relative condition of thecoil springs 14, 15.

For the purpose of providing yielding means to be as- Vsoc'iated withthe supporting housing 5 and the slide element 19 for biasing said slideelement 19 toward the above described engaged position thereof inengagement Vwith the coil spring 15 so as to removably maintain both ofsaid coil springs 14, 15 in the above described second condition orposition thereof shown in FIGS. 2 and 4, a vcompression spring 29 isinterposed between la detent 30 dened on the dog 22 of the slide element19 and an opposed and aligned detent 31 defined by the side wall 7 ofthe supporting housing 5. In the position of the compression spring 29shown and described, the axis thereof is Vdisposed in general normalityto thelongitudinal axes of the elongated coil springs 14, 15 so thatVthe coil spring 15 is normally biased in such manner as 4to define the.above described second condition or relative position of Ythe coilsprings 14, 15. It should be noted with particular emphasis that whenthe coil springs 14, 15 are in the above described second relativecondition thereof, they are thereby orientated so that the coil spring14 is engaged by the keeper element .1 during initial opening movementof the door member A with respect to the jamb member B so that generallyconcerted lateral deection is imparted to both of the coil springs 14,15 during said initial opening movement of the door member A. Morespecifically with respect to the deflection of the coil springs 14, 15during the initial opening movement of the door member A when the coilsprings 14, 15 are in said second condition thereof, the coil spring 1Sis actually deflected by the keeper element 1 and said deflection isthen imparted to the engaged intermediate portion 28 of the coil yspring15 so as to move said intermediate portion 28 of the coil spring 15along the abutment surface 27 of the slide element 19 during saidinitial opening movement of the door member A. It should be stated thatin accordance with present practices, the orientation of the coilsprings'14, 15 when the same are in either the -above described onecondition thereof or the second condition thereof is such that lateraldeflection is imparted only to the coil'spring 14 during nal closingmovement of the door member A with respect to the jamb member B, asshown in FIG. 7.

Having specically described my invention, it might be helpful to commentwith respect to the operative simplicity thereof. Generally speaking, anovel friction catch 3 has been provided in which the force required toopen the door member A upon which the friction catch 3 is secured ismaterially less when the friction catch 3 is in FIG. 4 of the drawingsshows the latch mechanism 4 and Vthe door member A in the closedposition thereof, and

FIG. 5 is illustrative of a position of the friction catch 3 duringinitial opening movement of the door member A when the door member A isopened from the outside thereof, it being understood that theterminology inside and outside corresponds to the inner face a and theouter face b of the door member A. The illustration of FIG. 5 isintended to correspond to the situation described in the introduction tothis specication wherein it is desirable that amaterially greater forcebe required to open the door member A from the outside thereof than theforce required to open the door member A from the inside thereof, theterminology outside and inside not being intended to be a limitationwith respect to the relative positioning of the door member Arwithrespect to the jarnb member B, but only being given the connotationdescribed above. It is noted therefore with respect to Y'FIG. 5 that thefriction catch Y3: is shown therein in the above described secondcondition thereof so that the ,opening of the door member A 4from theoutside thereof requires a deection of both of the coil springs 14, 15.

Referring to FIG. 6, the same is illustrative of the conditions presentwhen it is desired to open the door nmember A Vfrom the inside thereof,the obnoxious pressure (noted in the introduction to this l specication)between the door member A and another door (not shown, vand associatedwith the jamb member B) being obviously previously released in thissituation by the opening of said other door. It `will be noted withrespect to FIG. 6 that when the -knob 21 of the slide element 19 ismoved in a direction away from the coil spring 15, the abutment surfaceof the slide element 19 is removed from its engagement with thegenerally intermediate portion 28 of the coil spring 15 and the coilusprings 14, 15arev then disposed in the above described one conditionthereof wherein said springs14, 15 are in laterally spaced generallyparallel relationship. Obviously, in this condition of the springs 14,15, the force required to open the door memberA need only be suflicientto deect the coil spring 14. It should also be noted that FIG. 7 isillustrative of the position of the friction catch 3 du-ring finalclosing Vmovement of the door member A. In this situation, only arelatively small force is required to close the door `member A, withoutregard towhether the coil springs 14, l5 are disposed in either of theabove described one condition `or second condition thereof. Obviously,the coil springs 14, 15 of the friction catch 3 will usually' bedisposed in the second above described spaced condition thereof shownparticularly in FIGS. 4, 5 and 7, this being due to the biasing of theslide element 19 toward the coil spring 15 by the compression spring 29.

This invention has been thoroughly tested and found to be completelysatisfactory for the accomplishment of the above objects; and while Ihave shown and described above a preferred embodiment thereof in whichthe principles of the present invention have been incorporated, I wishit to be specifically understood that the same may be modified withoutdeparture from the scope and spirit of the appended claims.

What I claim is:

l. In a latch mechanism for latching a door member mounted for openingand closing movements relative to a cooperating jamb member, and inwhich one of said members is provided with a rigidly mounted keeperelement, the improvement of a friction catch, said improvementcomprising supporting structure rigidly secured to the other of saidmembers, a pair of elongated coil springs carried by said supportingstructure with their respective end portions iixedly disposed withrespect to said other of said members, said springs being disposed inone condition in generally laterally spaced generally parallelrelationship with one another, said coil springs when in said onecondition being so orientated that one of said springs is engaged bysaid keeper element during initial opening movement of said door memberwith respect to said jamb member so that lateral deflection is impartedto said one spring, and a movable abutment element mounted on saidsupporting structure for movements toward and away from said other ofsaid springs between a spaced position in spaced relationship to saidother of said springs and an engaged position wherein said abutmentelement is disposed in engagement with a generally intermediate portionof said other of said springs so as to displace said intermediateportion of said other of said springs into engagement with said one ofsaid springs and thereby define a second condition of said springs, saidcoil springs when in said second condition being so orientated that saidone spring is engaged by said keeper element during initial openingmovement of said door member with respect to said jamb member so thatconcerted lateral deection is imparted to both of Said coil springsduring said movement, whereby the force required to deflect both of saidsprings and open said door member when said springs are in said secondcondition is materially greater than the force required to deflect saidone spring and open said door member when said springs are in said onecondition.

`2. In a latch mechanism for latching a door member mounted for openingand closing movements relative to a cooperating jamb member, and inwhich one of said members is provided with a rigidly mounted keeperelement, the improvement of a friction catch, said improvementcomprising supporting structure rigidly secured to the other of saidmembers, a pair of elongated coil springs carried by said supportingstructure with their respective end portions iixedly disposed withrespect to said other of said members, said springs being disposed inone condition in generally laterally spaced generally parallelrelationship with one another, said coil springs when in said onecondition being so orientated that one of said springs is engaged bysaid keeper element during initial opening movement of said door memberwith respect to said jamb member so that lateral deection is imparted tosaid one spring, and a movable abutment element mounted on saidsupportinU structure for movements toward and away from said other ofsaid springs between a spaced position in spaced relationship to saidother of said springs and an engaged position wherein said abutmentelement is disposed in engagement with a generally intermediate portionof said other of said springs so as to displace said intermediateportion of said other of said springs into engagement with said one ofsaid springs and thereby deline a second condition of said springs, saidcoil springs when in said second condition being so orientated that saidone spring is engaged by said keeper element during initial openingmovement of said door member with respect to said jamb member so thatgenerally concerted lateral deflection is imparted to both of said coilsprings during said movement, whereby the force required to deect bothof said springs and open said door member when said springs are in saidsecond condition is materially greater than the force required to deectsaid one spring md open said door member when said springs are in saidone condition, the orientation of said coil springs when the same are ina selection of Said one condition and sai-d second condition being suchthat lateral deflection is imparted only to said one spring during nalclosing movement of said door member with respect to said jamb member.

3. In a latch mechanism for latching a door member mounted for openingand closing movements relative to a cooperating jamb member, and inwhich said jamb member is provided with a rigidly mounted keeperelement, the improvement of a friction catch, said improvementcomprising a supporting housing rigidly secured to said door member, apair of elongated coil springs carried by said supporting housing withtheir respective end p0rtions xedly disposed with respect to said doormember, said springs being disposed in one condition in generallylaterally spaced generally parallel relationship with one another, saidcoil springs when in said one condition being so orientated that one ofsaid springs is engaged by said keeper element during initial openingmovement of said door member with respect to said jamb member so thatlateral deection is imparted to said one spring, and anabutment-surface-dening slide element mounted on said supporting housingfor movements toward and away from said other of said springs between aspaced position in spaced relationship to said other of said springs andan engaged position wherein the 'abutment surface of said slide elementis ydisposed in engagement with a generally intermediate portion of saidother of said springs so as to displace said intermediate portion ofsaid other of said springs into engagement with said one of said springsand thereby define a second condition of said springs, said coil springsin said second condition being so orientated that said one spring isengaged by said keeper element during initial opening movement of saiddoor member with respect to said jamb member so that concerted lateraldeflection is imparted to both of said coil springs during saidmovement, whereby the force required to deilect both of said springs andopen said door member when said springs are in said second condition ismaterially greater than the force required to deflect said one springand open said door member when said springs are in said one condition.

4. The structure defined in claim 3 in which the orientation of saidcoil springs when the same are in a selection of said one condition andsaid second condition is such that lateral deflection is imparted onlyto said one spring during iual closing movement of said door member withrespect to said jamb member.

5. In a latch mechanism for latching a door member mounted for openingand closing movements of its free edge relative to a cooperating jambmember, and in whichV said jamb member is provided with a rigidlymounted keeper element, the improvement of a friction catch, saidimprovement comprising a supporting housing rigidly secured to said doormember, a pair of elongated coil springs carried by said supportinghousing with their respective end portions iixedly disposed with respectto said door member, said springs being disposed in one condition ingenerally laterally spaced generally parallel relationship with oneanother, said coil springs when in said one condition being soorientated that one of said springs is engaged by said keeper elementduring initial opening movement of said door member with respect to saidjamb member so that lateral deection'is imparted to said one spring, anabutment-surface-dening slide element mounted on said supporting housingfor movement tolward and away from said other of said springs between aspaced position in spaced relationship to said other of said springs andan engaged position wherein the abutment surface of said slide elementis disposed in engagement with a generally intermediate portion of saidother of said springs so as to displace said intermediate portion ofsaid other of said springs into engagement with said one of said springsand thereby denne a second condition of said springs, and yielding meansassociated with said supporting housing and said slide element forbiasing said slide element toward said engaged position thereof, saidcoil springs when in said second condition being so orientated that saidone spring is engaged by said keeper element during initial openingmovement of said door member with respect to said jamb member so thatgenerally concerted lateral deflection is imparted to both of said coilsprings during said movement, whereby the force required to deect bothof said springs and open said door member when said springs are in saidsecond condition is materially greater than the force required to deectsaid one spring and open said door member when said springs are in saidone condition.

6. The structure defined in claim in which the orientation of said coilsprings when the same are in a selection of said one condition and saidsecond condition is such that lateral deection is imparted only to saidone spring during inal closing movement of said door member with respectto said jamb member.

7. The structure defined in claim 5 in which said supporting housing hasopposite sides, said elongated coil springs being carried by saidsupporting housing on the side thereof disposed adjacent the free edgeof said door member, and in which said yielding means comprises: a dogdefined by said slide element and projecting into said supportinghousing; aV deten-t defined by the side of said housing opposite theside thereof which carries said elongated coil springs; and acompression spring interposed between said dog and said detent anddisposed with its axis in general normality to the axes of saidelongated coil springs. v

8. In a latch mechanism for latching a door member mounted for openingland closing movements relative Y to a cooperating jamb member, and inwhich said jamb ment, the improvement of a friction catch, saidimprovement comprising a supporting housing rigidly secured to said doormember, a pair of elongated coil springs carried by said supportinghousing on the side thereof disposed adjacent the free edge of said doormember and with the respective end portion of said coil springs beingfixedly disposed with respect to said door member, said springs beingdisposed in one condition in generally later- 'ally spaced generallyparallel relationship with one another, said coil springs when in saidone condition being soorientated that one of said springsis engaged bysaid keeper element during initial opening movement of said door memberwith respect to said jamb member so that lateral deflection is impartedto said one spring in a direction, generally toward said spaced otherspring, an abutment-surface-dening slide element mounted on saidsupporting housing for movement toward and away from said other of saidsprings between a spaced position in spaced relationship to said otherof said springs and an engaged position wherein the abutment surface ofsaid slide element is disposed in engagement with a generallyintermediate portion of said other of said springs so as to ldisplacesaid intermediate portion of said other of said springs into engagementwith said one of said springs and thereby define a second condition ofsaid springs, and

yielding means associated with said supporting housing and said slideelement for biasing said slide element toward said engaged positionthereof, said coil springs when in said second condition being soorientated that said one spring is engaged by said keeper element duringinitial opening movement of said door member with respect to said jambmember so that said one spring is deflected and said deflection isimparted to said engaged intermediate portion of saidother spring so asto move said intermediate portion of said spring 4along the abutmentsurface of said slide element during said initial opening movement,whereby lthe force required to `deflect both of said springs andv opensaid door member when said springs are in said second condition ismaterially greater than the force required to deflect said one springand said door member when said springs are in said one condition.

Coulson Apr. l5, 1960 Hafstad Oct. 25, 1960

